3.5" vs 2.5''

LIVINtheLIFE · May 22, 2015

As the title says im looking at either a 3.5 or a 2.5 for my 2015 Sierra. Now my options are to do a 2.5'' RC lift and install myself and get a wheel alignment done which will be roughly $300 but it may void warranty(even tho my dealer said that's fine as long as it is installed properly, but that's not on paper). Or my dealer will install the 2.25" readylift kit for $500, this will include my wheel alignment and they will honor all my warranty.

But what caught my eye was the 3.5" RC kits as well, there are 2. One with and one without the uni-ball moog joints. Does anyone have experience between the 2? More or less is the uni-ball joint that much better then factory? If the arm of the new joint is the same then the ball joint will still be at the same angle after the lift so is it worth it?

I will be running 285/70-17 or 295/70-17 tires one factory rims for now. But I have a set of 285/75-17's almost brand new in my garage... think they will work with just a level?

Bare with me on this one, im very mechanically inclined but im new to GMC/Chevy. Ive been a Dodge guy my whole life and this is my first ever GM, just wanna do it right the first time!!

Chris · May 22, 2015

Either way you go, suspension warranty is voided if the part is PROVEN to be the cause of part failure . Dealership can not retain GM warranty with aftermarket parts. They can just provide their own. And if you go that route, get that shit in writing. No ifs, ands, or buts. Make sure you have it in writing and save that paperwork.

nadrojcote · May 22, 2015

If you go with the 3.5" get the upper control arm kit. 3.5" without them is really hard on the ball joints. I have their 3.5" upper control arms with my 2" rancho quicklifts because I didnt like the ball joint angles.

Also their upper control arms come with moog ball joints, not uniballs. Two different things.

You'll be able to fit those tires with anything over 2" even the 75/17s. If you go with a 3.5" kit all those tires are going to look too small in my opinion.

285/70r17 are actually less diameter than my 22's. So if you look at my truck my tires are actually bigger than what you will be running and I only have a 2" level. Your 285/75r17 are an inch bigger in diameter than mine.

LIVINtheLIFE · May 22, 2015

Either way you go, suspension warranty is voided if the part is PROVEN to be the cause of part failure . Dealership can not retain GM warranty with aftermarket parts. They can just provide their own. And if you go that route, get that shit in writing. No ifs, ands, or buts. Make sure you have it in writing and save that paperwork.

Thanks, I'm thinking the best route is the factory installed ReadyLift then. I specifically asked them about ball-joints and they said they will honor their warranty with this kit factory installed. I'm staying away from the 3.5" kit just because of gas mileage and less stress on parts.

If you go with the 3.5" get the upper control arm kit. 3.5" without them is really hard on the ball joints. I have their 3.5" upper control arms with my 2" rancho quicklifts because I didnt like the ball joint angles.

Also their upper control arms come with moog ball joints, not uniballs. Two different things.

You'll be able to fit those tires with anything over 2" even the 75/17s. If you go with a 3.5" kit all those tires are going to look too small in my opinion.

285/70r17 are actually less diameter than my 22's. So if you look at my truck my tires are actually bigger than what you will be running and I only have a 2" level. Your 285/75r17 are an inch bigger in diameter than mine.

I must've read the uniball joints on a different kit. My bad. Either way the 3.5" isn't worth it to me. More stress on parts for only 1" of lift, and with the replaced moog joints then warranty goes out the window anyways. Im curious on how the 285/70's are less in diameter then your 22's tho?? Correct me if im wrong but my 285/75's are almost exactly 1'' in diameter bigger then the 285/70's.

Chris · May 22, 2015

Once again just because the dealer installs it does not mean it will be warrantied. Get paperwork on it to cover your ass if ever needed

nadrojcote · May 22, 2015

Thanks, I'm thinking the best route is the factory installed ReadyLift then. I specifically asked them about ball-joints and they said they will honor their warranty with this kit factory installed. I'm staying away from the 3.5" kit just because of gas mileage and less stress on parts.

I must've read the uniball joints on a different kit. My bad. Either way the 3.5" isn't worth it to me. More stress on parts for only 1" of lift, and with the replaced moog joints then warranty goes out the window anyways. Im curious on how the 285/70's are less in diameter then your 22's tho?? Correct me if im wrong but my 285/75's are almost exactly 1'' in diameter bigger then the 285/70's.

well the 3.5" kit probably causes less stress because it drops the diff I believe. Also their control arms come with moog ball joints that have a life time warranty.

my tires are 305/45r22 which are 32.81", 285/70r17 are 32.71" and 285/75r17 are 33.83"

http://www.1010tires.com/Tools/Tire-Size-Calculator/305-45R22/285-70R17/285-75R17

LIVINtheLIFE · May 22, 2015

well the 3.5" kit probably causes less stress because it drops the diff I believe. Also their control arms come with moog ball joints that have a life time warranty.

my tires are 305/45r22 which are 32.81", 285/70r17 are 32.71" and 285/75r17 are 33.83"

http://www.1010tires.com/Tools/Tire-Size-Calculator/305-45R22/285-70R17/285-75R17

Yea I knew the dimensions of my 2 sets just didn't know exactly what yours were. 0.10" isn't much a difference so I should be safe with my 285/75's instead of going and buying new tires.

Once again just because the dealer installs it does not mean it will be warrantied. Get paperwork on it to cover your ass if ever needed

Yes I understood what you said and that's what I meant by the factory installed Readylift 2.25" kit WILL be covered with paperwork. My local dealer stocks,supplies and installs ReadyLift products and if I go to them they will provide me with a receipt and paperwork stating I will still be covered. It just costs an extra $200~ is all.

LIVINtheLIFE · May 22, 2015

well the 3.5" kit probably causes less stress because it drops the diff I believe. Also their control arms come with moog ball joints that have a life time warranty.

my tires are 305/45r22 which are 32.81", 285/70r17 are 32.71" and 285/75r17 are 33.83"

http://www.1010tires.com/Tools/Tire-Size-Calculator/305-45R22/285-70R17/285-75R17

Also dropping the diff will only correct your CV shaft angles. Ball joint angles will be even more out then the levelling kits. To correct ball joints you would need larger steering knuckles and/or drop brackets for lower control arms.

nadrojcote · May 22, 2015

I believe it drops the diff and the lower control arm mounts doesn't it? I could be wrong. Also extends the sway bar links. Which would take care of all other angles that aren't fixed by the upper control arms.

LIVINtheLIFE · May 23, 2015

That's possible....im just going by what I see in the kits pictures. I didn't see any brackets that relocate your lower control arm. I could be wrong as well but it almost looks like to me going with the 3.5" or 4" kits is a big no no. I don't even know if your caster wheel alignment could ever be fixed with that much angle. Your almost better off to go with a 5" that has drop brackets so you can fit 35's without trimming.